The present invention relates to a three-dimensional measuring method and a surveying system, which has a simple configuration and which can perform three-dimensional measurement over a wide range.
Conventionally, for three-dimensional (hereinafter referred as “3D”) measurement of a construction object, a total station or a 3D scanner is used. However, a measuring instrument as such is designed to measure a distance by projecting a distance measuring light and by receiving a reflected distance measuring light. In this respect, it is necessary that an entire measurement area can be overlooked from a point of installation of the measuring instrument. For this reason, there are many restrictions in the place of installation, and further, in a case where a dead area is present for the measurement of an object to be measured, the changing of the installation of the measuring instrument is necessary.
Further, in a case where the object to be measured is a construction object with complicated structure, there may be many portions which cannot be measured due to a problem of a poor field of vision.
In this case, the object to be measured must be measured by installing the measuring instrument at different places, and a 3D model of the object to be measured must be prepared by synthesizing measurement results (i.e. 3D coordinates) obtained by measuring at each of the positions of installation (i.e. measurement position). On the other hand, reference coordinates of the measurement results obtained by measuring at each of the places are the positions of each of the measuring instruments. In a case where the 3D model is prepared, the measurement results obtained at each of the places must be converted to unified coordinates by coordinate conversion.
Further, when converting to unified coordinates by coordinate conversion, a coordinate conversion must be performed to the unified coordinates, a measurement is performed with respect to a distance and an angle between each of the measurement positions each time the measurement position is changed and a coordinate conversion must be performed to the unified coordinates. For this reason, there are problems in that the more complicated the construction object is, the more complicated the working process becomes.
Further, there is a method of synthesizing by using three or more known points, which are called reference points, other than the method of measuring a distance or an angle between the measurement positions. However, there have been problems in that the coordinates cannot be determined or that there are many cases which are complicated.